三维激光扫描辅助隧道大变形控制研究OA北大核心

In order to solve the problem that in the study of high ground stress soft rock large deformation tunnel control,the traditional monitoring methods have limited sections and points,the monitoring results are point by point,and it is difficult to find the maximum and minimum average deformation,which cannot provide effective data support for the optimization of tunnel initial support adjustment.Based on Shanenshan tunnel No.2,a 3D laser scanner is used to monitor the holographic deformation of the tunnel initial support,to obtain a full picture of the deformation of the tunnel initial support,and to analyze the settlement convergence and section profile deformation.Meanwhile,based on the 3D laser deformation monitoring results,we design the SRLD support structure to adapt to the deformation characteristics of the tunnel,and control the damage of the initial support of soft rock large deformation tunnel.The results show that:(1)the variance of settlement monitoring between 3D laser scanner and total station is 3.03 mm,and the variance of convergence monitoring is 3.42 mm,the monitoring accuracy of the two instruments is approximate.(2)the monitoring results of 3D laser scanner show that the left side of the initial support appears to be affected by the shear-slip zone of the surrounding rock with local bulging problem,the bulging influence range is from the left arch foot to the left arch waist,and along the mileage direction shows obvious spatial and temporal effect.(3)based on the 3D laser scanner monitoring results,the asymmetric design of the energy-limited support structure,compared with the design support section,has achieved a better control effect on the initial support damage,while the development of the tunnel deformation rate is judged by the deformation acceleration,which can avoid the phenomenon of false type of warning in the cumulative deformation and deformation rate warning.